September 26, 1895] 



NA TURE 



OJ/ 



tures is described. Oxy-salts have been chiefly examined, the 

 most interesting results lieing ol)taine<l with the chlorates and 

 iodates of potassium and silver. Willi potassium chlorate action 

 takes place at the ordinary temperature, chlorine being evolved, 

 but no potassium chlorate being forme<l. With silver chlorate, 

 chlorine is also evolved, but some chlori<le is obtained. I'otassium 

 iodate yields iodine but no potassium iodide at a low tempera- 

 ture, while silver iodate is completely converted into iodide, no 

 iodine being liberated, or silver nitrate formed. It is suggested 

 that these results tend to show a difference in constitution between 

 the silver and potassium salts. 



Prof. Clowes gave an account of further experiments on the 

 I'espirability of air, in which a cantlle flame has Ijurnt till 

 it is extinguished. He finds that an atmosphere, which con- 

 tains oxygen i6"4 per cent., nitrogen 8o'5 per cent., carbon 

 dioxide 3'I per cent., will extinguish a candle flame, but is .still, 

 according to the experiments of llaldane, not only respirable, 

 but would be breathed by a healthy person for some time without 

 injury. An atmosphere which extinguishes a coal-gas flame, 

 however, appears to apj^roach closely to the limits of respir- 

 ability, as far as the proportion of oxygen which it contains is 

 concerned. The candle and lamp flames should be discarded as 

 tests of the respirability of air in favour of the coal-gas flame. 



A paper was re.id by Mr. D. J. V. Berridge, on the action of 

 light upon the soluble metallic iodides in presence of cellulose, 

 in which it was shown that the amount of iodine liberated from 

 ]iotassium iodide by the combined action of ligb", air and 

 moisture, is greatly increaseil by the presence of cellulose, this 

 substance probably combining with the potassium hydrate 

 liberated in the reaction. By investigating the conditions of 

 formation of the chocolate stain obtained when note-paper con- 

 taining starch, and .soaked in potassium iodide solution, is exposed 

 to light, evidence is obtained of the formation of a Iri-ioflide of 

 potassium. The iodides of sodium, calcium, stronliuni, barium, 

 iron, and zinc, all behave like the potassium salt ; cadmium seems 

 ulone unable to form a higher iodide. 



Dr. C. K. Kohn read the second report of the Committee on 

 '|uantitative analysis by means of electrolysis. The bibliography 

 of the subject has been completed. The experimental work 

 has been carefully organised, and the results on the determina- 

 tion of bismuth and of tin are nearly complete. 



Sir II. E. Roscoe presented the report of the Committee 

 appointed to prepare a new series of wave-length tables of the 

 spectra of the elements. 



Some interesting communications were made to a joint sitting 

 of Sections A and B ; and the account of these, which we give 

 in our report of the work of»the former Section, is supplemented 

 by the following notes on Dr. Gladstone's and Prof. Schuster's 

 communications. 



Dr. Gladstone's paper v/as on specific refraction and the 

 periodic law, with special reference to argon and other 

 elements. In former years he had shown that the specific 

 refractive energies of the elements in general were, to a certain 

 extent, a periodic function of their atontic weights. 'iVith 

 regard to argon, the specific refractive energy of argon gas as 

 reckoned by Lord Raylcigh's data is OT59. At the suggestion 

 ■ if Deelcy, the bearing of this result on the atomic weight of 

 argon was considered. If the atomic weight be I9'94, the 

 molecular refraction will be 3'I5. This figure is almost identical 

 with that belonging to oxygen and nitrogen gas, and differs 

 considerably from that of calcium, which has a molecular 

 refraction of lO'O and a .specific refractive energy of 0'248. 

 These facts tend to suggest an atomic weight of 20 for argon, 

 and to place it in the vicinity of the alkali metals. 



The discussion, which was opened by Prof. Schuster, on the 

 evidence to be gathered as to the simple or compound nature of 

 a gas from the constitution of its spectrum, dealt with matters 

 of rather more jihysical than chemical bearing. Of special 

 interest to chemists, however, was the evidence cited by Prof. 

 Schuster for con.sidering that the variations noticed in the spectra 

 of sodium, nitrogen, and mercury under different conditions 

 were due to difierences in atomic aggregation. 



Monday's sitting was devoted to a discussion, held in conjunc- 

 tion with Section K (Botany), on the relation of agriculture to 

 science. It was introduced by Prof. R. Waringlon in a paper 

 entitled, " How shall .agriculture best obtain the help of science ? " 

 This was devoted to a consideratiim of the best means for 

 diflusing a knowledge of the scientific principles of agriculture. 

 Certain things could be usefully done by a Board of Agriculture, 

 and others by County Councils. The formation of a really 



NO. 



1352, VOL. 52] 



complete agricultural and fiorticultural library, freely open to the 

 public, and the maintenance of an English agricultural journal, 

 are matters which might fall to the Board of .\griculture. The 

 advantages to be derived from a (iovernment laboratory 

 and ex])erimental station were dwelt upon. Local stations and 

 secondary agricultural schools shoultl be maintained by the 

 County Councils, who also should inspect the technical 

 instruction in their locality. The foundation of habits of 

 observation and logical reasoning must be laid in the elementar}' 

 school if higher instruction is aftersvards to be given. Higher 

 qualifications should be required for agricultural lecturers than is 

 at present the ca.se. 



Mr. T. Hendrick conlriliuted a second paper. He spoke of 

 the apath)- and even hostility to science shown by the practical 

 agriculturist, and considered the reasons for this attitude. 



In other countries national systems of agricultural education 

 and research have been founded by the State. It is hopeless to 

 look to local effort and sui>port, because the practical man 

 expects immediate results, and results out of all proportion to 

 the time and money expended in obtaining them. The time has 

 come when the State must take part in the work and devote 

 to it much larger sums than at present. 



Mr. Thiselton-Dyer said that the matter had been carefully 

 considered by the last Government. It was difficult, however, 

 to persuade the Treasury that agriculture was entitled to receive 

 special ai<l of a kind not given to any of our other great 

 industries, such as iron and textiles. Personally he looked to 

 individual efl'orl and munificence to supply what was needed. 



Prof. Marshall Ward pointed out that it was of extreme im- 

 portance that the results of any investigations should be made 

 known at once and accurately to the practical man, and 

 this was work which might very well be undertaken by Govern- 

 ment, but he deprecated any direction or control from a Govern- 

 ment department in any matters of original research. 



Prof. J. R. Green pointed out the necessity for investigations 

 on vegetable physiology, as bearing on the growth of crops. 



Sir Douglas Galton agreed with Mr. Dyer that agriculturists 

 must look to themselves for help, rather than to the Govern- 

 ment. The obtaining of really good teachers was the great 

 difiiculty. 



Lord Walsingham spoke of the difficulty in producing crops 

 which would realise a profit. Wheat-growing was unprofitable 

 in England, and his own attempts to grow tobacco were 

 frustrated by the heavy duty. 



Sir J. Evans and Sir H. Roscoe spoke of the work of the 

 County Councils, and Prof. Perceval gave an account of the 

 courses at Wye College. 



Mr. T- I-ong considered that schools and colleges for boys and 

 youths and demonstration plots for adult farmers were the best 

 means of bringing home the benefits arising from the application 

 of science to agriculture. 



Mr. J. R. Dunstan, in a paper on the subject under discussion, 

 contended that courses of lectures were necessary as pioneer work. 

 Unless farmers have a general knowledge of the principles of 

 science, they cannot really understand the results of experi- 

 ments. 



Prof. Liveing advised the co-operation of County Councils in 

 maintaining a central experimental station. He described the 

 system of agricultural teaching adopted at Cambridge. 



Mr. Avery gave some account of the agricultural side attached 

 to the .\shburton School in Devon, and spoke of the difiiculty 

 of obtaining pupils. 



Mr. T. .S. Dymond emphasised the necessity of a knowledge 

 of scientific principles, if farmers were to projjcrly understand 

 experimental results. 



Mr. C. H. Bothamley considered agricultural sides to secondary 

 schools much better than schools restricted to farmers' sons. The 

 value of demonstration plots, as distinguished from exijerimental 

 plots, was very great. 



Prof. Warington, in reply, remarked that the whole agricultural 

 position was such that if anything was to be done, it must be 

 done at once, they could not afl'ord to wait. 



.Mr. T. B. Wood gave an account of work at the experi- 

 mental plots in Suffolk and Norfolk. The experiments in 

 Suffolk are conducted at two stations with soils typical of large 

 areas in the neighbourhood, viz. at Higham, where the soil is 

 thin and light with a chalk sul)-soil, and at Lavenham, where it 

 is a much deeper loam. The experiments at both stations consi.st 

 in the growth of various crops in rotation with various manures. 

 Each year a report of these experiments is printed and circulated, 



